In order to further optimize the fuel consumption of commercial aircraft, the manufacturer is attempting to reduce the aerodynamic drag of key aerodynamic effective surfaces, such as the leading edges of the airfoils, the front edge of the horizontal tailplane, or the leading edge of the vertical tailplane. Undesired turbulent flows exist in the area of the leading edges in a region near the surface, which increase aerodynamic drag, and consequently the fuel consumption of the aircraft.
In order to reduce the aerodynamic drag, it is necessary that the turbulent flows in a region near the surface of the aerodynamic effective surfaces of an aircraft be significantly reduced. For example, technologies from the area of bionics can be used for this purpose. It is known to provide airfoils of aircraft with coatings having a surface quality made to mimic the skin structure of sharks, for example. The disadvantage here is that the coatings, for example which can be applied as plastic films or paints, are subject to strong erosive processes during flight operations, which are associated with considerable wear, and require a resultant high maintenance outlay, the costs of which can at least partially nullify the achievable savings in fuel again.
Another alternative is to give the leading edges of the relevant aerodynamic effective surfaces a sandwich design, so as to form a plurality of cavities. In this alternative, the area of the leading edges has a micro-perforation, through which the inflowing air gets into the cavities lying further back, and from there can be centrally suctioned by means of a pump to reduce the aerodynamic drag. Because the cavities each have boreholes with a diameter that varies from cavity to cavity, different pressures come about in the cavities. As a result, varying volumetric air flows pass through the cavities, despite the central suction. However, the disadvantage in this embodiment is predominantly the sandwich design of the leading edges of the aerodynamic effective surfaces, which is technically extremely demanding to manufacture. The area in which the inflowing air is suctioned near the surface is not confined to the area of the leading edges of the respective aerodynamic effective surface.